Hi,
You can't set the object Id, that would cause too much trouble for you and Parse.
Whyt would setting the object in your case would be useful? objectId is a byproduct, it's always something you catch and store for reference so it doesn't matter the actual id, you only cache it.
In your case ( If I understood), when you create your character class, store that object Id when you create it, that's all, parse will take care of creating that object id for you.
Bye,
Jean